1. Field of the Invention
The invention relates to a radial compressor unit.
2. Description of the Related Art
From DE 37 29 486 C1 a compressor unit for compressing gas is known, which comprises multiple compressor stages and a drive embodied as an electric motor. According to this prior art, the compressor stages and the drive are arranged in a common, gas-tight housing. In DE 37 29 486 C1 it is proposed to guide compressed gas over a surface cooler in order to cool the compressed gas. Here, the cooling of the compressed gas acts with the help of the surface cooler between two compressor stages.
From DE 10 2007 019 264 A1 it is known to remove compressed gas in the region of a compressor stage of a compressor unit and to use the compressed gas as cooling gas for a component to be cooled. Here, the gas that is removed as cooling gas is to be free of contaminations such as, for example, particles and/or liquids. It is desirable, furthermore, that the removed gas has as high a pressure as possible. In order to remove cooling gas that is as pure as possible from a compressor stage of the compressor unit, it is proposed, according to the prior art according to DE 10 2007 019 264 A1, to remove the cooling gas via a removal channel which, adjacently to an impeller, which is also called rotor, and adjacent to a diffuser section of a flow channel running downstream of the impeller, branches off a wheel lateral space. In this way, relatively pure cooling gas, which contains few contaminations, can be removed but the removed cooling gas however only has a relatively low pressure.
There is a need for a radial compressor unit, on which, in the region of a compressor stage, cooling gas can be removed, which, on the one hand has relatively few contaminations, and, on the other hand a relatively high pressure.